Readability is all the rage these days. Internet tools abound that check how easy it is to read your copy. There’s even one built into Microsoft Word. They’re great fun. But a word of caution, they may lead to a misjudgement of catastrophic proportion. So before you read Fifty Shades of Grey to the nearest 9-year-old, here’s a quick guide to the pros and cons of measuring your writing.

What is readability?

Readability means how easy something is to read. Being easy to read can be a good thing – complicated writing can make readers lose interest.

Great copy is a mixture of lots of different elements – like emotion, rhythm, or persuasion. Good writers instinctively combine them to create engaging content.

Readability is a quick way of checking how easy your words will be to digest.

Remember, though – readability can’t tell you anything about the content. You can have an easy to understand yet boring report, or you can have an imaginative novel that’s a challenging read.

So how do I know if something is readable?

There are formulae to measure how readable your text is. They count sentences, words, and syllables but each have different weightings.

The most common tests are:

Automated Readability Index (ARI)

Coleman-Liau Index

Dale-Chall Readability Formula

Flesch-Kincaid tests

Gunning-Fog Index

Simple Measure of Gobbledygook (SMOG).

Our favourite is the Flesch-Kincaid Grade Level, as it’s accurate and its built into Microsoft Word. Plus it sounds impressive. For the geeks out there, there’s a guide to using it at the end of this post.

It runs alongside your grammar check and gives you a score a the end. The score tells you which US school grade your writing is appropriate.

So Grade 6 would be right for an 11-year-old (and is about the score The Sun would get). Grade 10 is for 15-year-olds (and is about what The Economist gets).

A good score isn’t the only target to aim for, but it’s useful to know you’re on the right track.

OK I get it, show me the results

We put a selection of books and articles through the Flesch-Kincaid test. Remember, a lower number means it’s easier to read.

So what can we learn from the results?

Fifty Shades of Grey is easier to read than James and the Giant Peach.

So should you read it to your 9-year-old?

Well… no, of course not.

The numbers show that popular writing explains things simply, no matter how complex or mature the content is.

The Lord of the Rings is one of the most vast, epic books ever written. The world Tolkien created is huge and complex. But he still made the book more readable than The Tale of Peter Rabbit.

It’s also no surprise the non-fiction books and the news articles come out higher than the fiction books. Academics can’t resist a few big words. And journalists often write lengthy sentences with lots of commas. But even these challenging tomes and longform articles get a lower score than a lot of business writing we come across.

Time to name and shame

We trawled the web for business copy to test on the readability scale. A quick search for generic phrases like “award-winning legal services” was all it took to find plenty of complicated writing. We looked for pages with long sections of text to give a fair sample, usually “About Us”.

We chose some at random.

Then we put it all in a chart to prove a point.

Of course, it wasn’t all bad. But it was far too easy to find complicated writing.

Websites should be easy to read, with quick access to important information. People won’t read through long blocks of badly written text. They’ll move on to a competitor.

What does this mean for me?

If you’re writing a specialist report then aim for a similar score to the FT or the Economist. Email or flyers should be closer to Stephen King. There’s no excuse for your writing to be more complicated than a book of lectures from the father of quantum physics.

As Guardian editor Tim Radford said, “No one will ever complain because you have made something too easy to understand.” Make your copy as readable as possible. Then your exciting ideas and imaginative prose will have the best chance of engaging your readers.

So should I just write really short, simple sentences?

No. Readability is an indicator – it shouldn’t be a goal. Variety is just as important.

Our results show that Fifty Shades of Grey might be a readable book – but it’s not just short sentences. It has a sentence with 93 words. There are some complicated ideas and, obviously, lots of adult themes.

You can’t become a best seller just by using a few more full stops. But they can’t hurt.

Keep practising all aspects of your writing. Professional writers don’t really need to think about readability, it often comes naturally. But, for now, there are a few ways you can fix that urgent copy you should have finished yesterday.